TBA (15W108)

Interval colorectal cancers in the setting of the Bowel Cancer Screening Programme in South Eastern Health & Social Care Trust


Reed O, Loughrey MB, Ing G, Fitzsimmons G, Armstrong G, Owen T, Caddy G


Department of Gastroenterology, The Ulster Hospital, South Eastern Health & Social Care Trust


The introduction of bowel cancer screening programmes (BCSP) have been shown to reduce mortality of colorectal cancer (CRC) by 16%. BCSP using faecal-occult blood (FOB) testing was implemented in Northern Ireland in April 2010.


To retrospectively review patients who were diagnosed with CRC and to identify interval cancers. These were identified as two types: those arising in individuals during the screening interval after either a negative FOB test or after a positive FOB test and subsequent negative (for cancer) colonoscopy.


We retrospectively collected data over the last five years of patients diagnosed with CRC. This data was crossed referenced by Public Health with the bowel cancer screening database to see if patients had participated.


Data was collected from January 2011 to July 2015. A database of 475 patients was identified. To detect interval cancers we specifically looked at patients diagnosed from 2013 onwards and were able to analyse data from 254 patients. 62.2% (158) patients were diagnosed with colorectal cancer that did not attend screening / were non-responders. 21.3% (54) patients were diagnosed as a screen detected cancer. 15.7% (40) patients were subsequently diagnosed with CRC despite having either one or two negative FOBs. 2 patients (0.79%) were classified as interval cancers. One was thought to be missed pathology and the second was thought to be due to aggressive pathology.


Since commencing bowel screening within the SE Trust, we have detected 2 interval cancers. One of these is likely to be aggressive pathology type and one truly missed cancer.